Comparison of reverse passive latex agglutination test and immunoblotting for detection of staphylococcal enterotoxin A and B

qStaphylococcal foodborne diseases resulting from consumption of food contaminated with staphylococcal enterotoxins (SEs) produced by certain strains of Staphylococcus aureus are the second most common foodborne illnesses in the world. Analytical methods are essential for routine monitoring purposes and safeguard public health. Different methods for SE detection have been proposed although their use in a complex matrix is often limited by the presence of substances that interfere with tests. In this article reverse passive latex agglutination (RPLA) and immunoblotting methods based on specific antibodies and currently available for SE detection have been compared. Culture filtrates from enterotoxin S. aureus strains isolated from cheese samples were identified by SET-RPLA. Then the culture filtrates identified as staphylococcal enterotoxin A and staphylococcal enterotoxin B by RPLA test were analyzed with immunoblotting. The results obtained suggest that either SET-RPLA or immunoblotting may be applied to culture filtrates for the detection of SEs with good correspondence of results. Although SET-RPLA represents a simple method for routine monitoring purposes, a positive result by a rapid method (RPLA) is only regarded as presumptive and must be confirmed by standard methods (Feng 1996), such as immunoblotting method.